Sergio Aguero has revealed he may not be ready to start Manchester City's mouth-watering Premier League clash with Chelsea on Sunday.

The prolific striker came on as a second-half substitute when City started its top-flight campaign with a 3-0 victory at West Brom on Monday.

Argentina international Aguero returned for preseason training late due to his participation in the Copa America and has hinted that he may have to settle for an impact role off the bench at best against the champion.

"Whether I start or not remains to be seen," the former Altetico Madrid frontman told City's official website. "I'm trying to get there and be in top condition, but arriving for pre-season later having taken part in the Copa America with Argentina means I need some additional time.

"With the whole season in mind, what matters the most is that I get in top form and don't take any risks."

Chelsea finished eight points clear of second-placed City last season, but Aguero is expecting a more dramatic title race this time around. 

"One thing you can say about the Premier League is that every year, it gets better," he said. "Once again, many teams have made very important additions and that means there's no single rival for us this season.

"It'd be very naive to think that Chelsea will be the only team competing for the top position - there will be many of us and each one will challenge in their own style.

He added: "We'll stay hungry for glory, we'll do our jobs, we'll win all we possibly can and see where that takes us."